Segmented core motor stators having stator core structures in which segmented cores are connected in a circular shape are known as stators for brushless motors and AC motors. A segmented core motor stator includes a stator core structure in which a plurality of segmented cores are connected in an annular shape, and a coil winding wrapped on a salient pole (tooth) of each of the segmented cores in the stator core. The segmented cores are arranged in an annular shape in a state of mutual contact by an assembly tool, the end faces of the adjoining segmented cores are joined to each other by welding, bonding, or other means, and an annular stator core is produced.
In the method for assembling a segmented core motor stator disclosed in Patent Document 1, an engaging protrusion and an engaging groove are formed in an insulator attached to each of the segmented cores so that the segmented cores can be simply connected and fixed in an annular shape, and the segmented cores are connected and fixed in an annular shape by mechanically engaging the engaging protrusion and the engaging groove. In the segmented core stator of the motor disclosed in Patent Document 2, a segmented core engaging stop is formed in an annular resin stator cover, and the segmented cores arranged in an annular shape are inserted in the stator cover, producing an arrangement in which the segmented cores are held by the segmented core engaging stops, and the segmented cores are connected and fixed in an annular shape. In the stator core of the brushless DC motor disclosed in Patent Document 3, the segmented cores are inserted in a mold in an annular shape, the motor casing is molded from resin in this state, and the segmented cores are integrated.
A structure in which laminated plates formed of magnetic material are laminated and fixed is also known as a segmented core, as disclosed in Patent Document 4. Flat clamping is used as the method for fixing steel plates and other laminated plates. For example, a half-blanked dowel (protrusion) obtained by the half-blanking of a laminated plate in the thickness direction (lamination direction) is formed by a half-blanking procedure using a punch, and the laminated plates are connected and fixed to each other by pressure-fitting, and clamping and fixing, the half-blanked dowel of one laminated plate into a recess on the back surface of a half-blanked dowel of another laminated plate.    Patent Document 1: Japanese Laid-Open Patent Publication No. 2005-312119    Patent Document 2: Japanese Laid-Open Patent Publication No. 2004-266982    Patent Document 3: Japanese Laid-Open Patent Publication No. 2009-17746    Patent Document 4: Japanese Laid-Open Patent Publication No. 2001-95181